With a power density of 6.25 W/in.3, the SMQ400 power supplies deliver 400 W from a package measuring 2 in. high by 4 in. wide by 8 in. long (including an end-mounted fan and cover). Accepting inputs from 90 to 264 V ac, they come in eight models with outputs ranging from 12 to 54 V dc. Features include active power-factor correction and an array of protection circuitry. An optional constant-current version is also offered. Prices start at $139 each in lots of 1000.